ARS | Publication request: THE RELATIONSHIP OF THE RICE BLAST RESISTANCE GENES PI-TA AND PI-TA2

Submitted to: National American Phytopathology Meetings
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 2002
Publication Date: July 24, 2002
Citation: Jia, Y., Wang, Z., Fjellstrom, R.G. 2002. The relationship of the rice blast resistance genes pi-ta and pi-ta2 [abstract]. National American Phytopathology Meetings.P. 2002-0670-AMA.

Technical Abstract: Rice blast, caused by Magnaporthe grisea, is a serious disease worldwide. The rice Pi-ta gene is effective against M. grisea strains in a gene-for-gene manner and has been cloned. Pi-ta gene dominant markers were developed to determine whether the Pi-ta² blast resistance gene is at the Pi-ta locus. Historically, IB-49 resistance is conferred by the Pi-ta² gene in the cultivar Kaybonnet. A ratio of 3 resistant (R):1 susceptible (S) was observed in an F2 population of 349 individuals of Kaybonnet and Maybelle using blast race IB-49 that is presumed to contain AVR-Pita². The Pi-ta gene was only identified in resistant individuals. A ratio of 3 R:1 S was also observed in another F2 population of 280 individuals of Kaybonnet and M-204. Again, only resistant individuals contain Pi-ta. We suggest that Pi-ta and Pi-ta² may be the same gene.